Radiator cap for pressurized cooling systems



Oct. 31, 1967 F. MAY

RADIATOR CAP FOR PRESSURIZEI) COOLING SYSTEMS Filed Sept. 7, 1965 Hedda/f May BY K WWW) ATTORNEY United States Patent 3,349,954 RADIATOR CAP FOR PRESSURIZED COOLING SYSTEMS Fredrick May, P.O. Box 783, Seadrift, Tex. 77983 Filed Sept. 7, 1965, Ser. No. 485,470 3 Claims. (Cl. 220-86) ABSTRACT OF THE DISCLOSURE The present application discloses a radiator cap for pressurized cooling systems, said cap comprising in combination a cap body adapted for positioning on a radiator filler neck, a neck sealing unit provided at the underside of said cap body for preventing escape of coolant from the radiator until a predetermined coolant pressure has been reached, said neck sealing unit including a central open-ended tubular member extending slidably through said cap body and projecting above the same, and a normally closed filler valve provided at the upper end of said tubular member above the cap body, whereby coolant under pressure greater than radiator pressure may be injected through said filler valve and tubular member into the radiator without removal of said cap from the filler neck, said filler valve comprising a housing secured to the upper end portion of said tubular member in communication therewith and provided with a filler port, a spring in said housing, and a valve element in the housing biased by said spring to normally close said filler port, the filler valve being openable by external pressure applied to said valve element against the resiliency of said spring, said neck sealing unit including a guide of resilient material provided at the underside of said cap body and having said tubular member slidable therein, a centrally apertured disc member provided at the lower end of said tubular member, an annular neck sealing element secured to the underside of said disc member, and a compression spring interposed between said disc member and said cap body.

This invention relates to new and useful improvements in radiator caps for pressurized cooling systems of internal combustion engines, or the like, wherein the coolant is maintained under a predetermined, higher than atmospheric pressure in order to raise its boiling point and thus retard evaporation under normal operating temperatures.

Conventional radiator caps employed in such pressurized cooling systems are provided with a spring-biased sealing unit which seals the filler neck of the radiator and permits a predetermined coolant pressure to be built up before releasing the same to a filler neck overflow when that predetermined pressure is exceeded. While such conventional radiator caps fulfill their intended purpose, they suffer the disadvantage of suddenly releasing hot, pressurized coolant and vapor when they are removed from the filler neck in order that coolant may be added to the system, as is periodically required. Such sudden release of hot, pressurized coolant and vapor often causes serious burns to the attendant, unless elaborate precautions are taken in safeguard against burns or unless time is lost in allowing the system to cool oif before the cap is removed.

The principal object of the invention is to eliminate the disadvantage of conventional caps as above outlined and to permit coolant to be added to the radiator without the conventional necessity of removing the cap or depressurizing the system.

This object is attained by the provision of a radiator cap which in addition to its conventional facilities for sealing the filler neck of the radiator also includes a spring-biased, normally closed filler valve, through which coolant may be added to the system in a safe, convenient and expeditious manner, without depressurizing the radiator or removing the cap or waiting for the system to cool off.

The improved radiator cap of the invention is simple in construction, efficient in operation, and lends itself to convenient and economical manufacture.

With the foregoing more important object and features in view and such other objects and features as may become apparent as this specification proceeds, the invention will be understood from the following description taken in conjunction with the accompanying drawings, wherein like characters of reference are used to designate like parts, and wherein:

FIGURE 1 is a vertical sectional view of the radiator cap of the invention, taken substantially in the plane of the line 11 in FIGURE 2; and

FIGURE 2 is a top plan view thereof.

Referring now to the accompanying drawings in detail, the radiator cap of the invention is designated generally by the reference numeral 10 and is intended to be used in conjunction with a pressurized cooling system including a radiator 11 provided with the usual filler neck 12, the latter having an inturned annular flange or seat 13 at its lower end and an outturned and downturned annular lip 14 at its upper end, in accordance with conventional practice.

The cap 10 comprises a cap body 15 provided with the usual fingerpieces 16 at its diametrically opposite sides and with a marginal rim 17 which encircles the lip 14 of the filler neck. The rim 17 is equipped with inturned lugs 18 which engage cam-edged slots (not shown) in the lip 14, whereby to securely but removably retain the cap in position on the filler neck, all as is well known in the art. As is also conventional, a suitable gasket or seal 19 is provided at the underside of the cap body 15 to seat upon the upper edge of the filler neck lip 14, as will be readily understood.

A spring-biased filler neck sealing unit designated generally by the numeral 20 is also provided at the underside of the cap body 15, the sealing unit 20 comprising a central, open-ended tubular member 21 which extends slidably through and projects above the cap body. The tubular member 21 also passes slidably through a substantiallyfrusto-conical guide 22 which not only guides the sliding movement of the tubular member but also frictionally engages the same so as to prevent possible leakage around the member 21 and upwardly through the cap body 15. The upper end of the guide 22 is formed integrally with an outturned flange 23 which provides a seat for the upper end of a compression spring 24. The lower end of the spring 24 bears against a centrally apertured, disc-shaped member 25 which is provided at the lower end of the tubular member 21. An annular sealing element 26 of any suitable material is secured to the underside of the disc member 25, the function of the spring 24 being to urge the element 26 into sealing engagement with the inturned flange or seat 13 of the filler neck 12, thus maintaining coolant in the radiator 11 pressurized (above atmospheric pressure) until such time as the coolant pressure is sufficient to overcome the action of the spring 24. At that time the spring 24 is compressed, the sealing element 26 is unseated from the flange 13 and excessive coolant pressure is released through an overflow tube 27 which communicates with the interior of the neck 12.

The upper end portion of the tubular member 21 carries a filler valve assembly 28 which includes a substantially frusto-conical housing 29 secured to and in communication with the member 21. The top of the housing 29 is provided with a filler port or opening 30 which is normally closed by a valve element or plug 31 biased by a tapered compression spring 32 in the housing 29, as will be clearly understood. Since the tubular member 21 is open-ended, the interior of the housing 29 is in communication with the interior of the radiator 11 and the pressurized coolant therein, which may be on the order of 3 to 15 p.s.i. (above atmospheric pressure), assists the spring 32 in keeping the filler port 30 closed by the valve element 31.

When it is desired to add coolant to the system, as for example, water supplied by a hose under normal mains pressure which may range anywhere from to 60 p.s.i., the water supply hose is applied to the valve element 31 so that the water pressure causes the same to retract against the action of the spring 32, thus permitting the water to fiow through the tubular element 21 directly into the radiator, all without any necessity of cooling or de-pressurizing the system or removing the cap 10 from the radiator filler neck. In this manner coolant may be added to the system as required in a safe, convenient and expeditious manner, while retaining the radiator cap in place.

While in the foregoing there has been described and shown the preferred embodiment of the invention, various modifications may become apparent to those skilled in the art to which the invention relates. Accordingly, it is not desired to limit the invention to this disclosure and various modifications and equivalents may be resorted to, falling within the spirit and scope of the invention as claimed.

What is claimed as new is:

1. A radiator cap for pressurized cooling systems, said cap comprising in combination a cap body adapted for positioning on a radiator filler neck, a neck sealing unit provided at the underside of said cap body for preventing escape of coolant from the radiator until a predetermined coolant pressure has been reached, said neck sealing unit including a central open-ended tubular member extending slidably through said cap body and projecting above the same, and a normally closed filler valve provided at the upper end of said tubular member above the cap body, whereby coolant under pressure greater than radiator pressure may be injected through said filler valve and tubular member into the radiator without removal of said cap from the filler neck, said filler valve comprising a housing secured to the upper end portion of said tubular member in communication therewith and provided with a filler port, a spring in said housing, and a valve element in the housing biased by said spring to normally close said filler port, the filler valve being openable by external pressure applied to said valve element against the resiliency of said spring, said neck sealing unit including a guide of resilient material provided at the underside of said cap body and having said tubular member slidable therein, a centrally apertured disc member provided at the lower end of said tubular member, an annular neck sealing element secured to the underside of said disc member, and a compression spring interposed between said disc member and said cap body.

2. The device as defined in claim 1 wherein said neck sealing unit also includes a guide of resilient material provided at the underside of said cap body and having said tubular member slidable therein.

3. The device as defined in claim 1 together with an outturned flange provided integrally at the upper end of said guide, said flange constituting a seat for said compression spring.

References Cited UNITED STATES PATENTS 2,760,367 8/ 1956 Stromberg 22()44 3,035,436 5/1962 Johnson 220-44 3,155,292 11/1964 Webster 220-44 3,276,488 10/1966 Holmes 220-44 THERON E. CONDON, Primary Examiner.

RAPHAEL H. SCHWARTZ, Examiner. 

1. A RADIATOR CAP FOR PRESSURIZED COOLING SYSTEMS, SAID CAP COMPRISING IN COMBINATION A CAP BODY ADAPTED FOR POSITIONING ON A RADIATOR FILLER NECK, A NECK SEALING UNIT PROVIDED AT THE UNDERSIDE OF SAID CAP BODY FOR PREVENTING ESCAPE OF COOLANT FROM THE RADIATOR UNTIL A PREDETERMINED COOLANT PRESSURE HAS BEEN REACHED, SAID NECK SEALING UNIT INCLUDING A CENTRAL OPEN-ENDED TUBULAR MEMBER EXTENDING SLIDABLY THROUGH SAID CAP BODY AND PROJECTING ABOVE THE SAME, AND A NORMALLY CLOSED FILLER VALVE PROVIDED AT THE UPPER END OF SAID TUBULAR MEMBER ABOVE THE CAP BODY, WHEREBY COOLANT UNDER PRESSURE GREATER THAN RADIATOR PRESSURE MAY BE INJECTED THROUGH SAID FILLER VALVE AND TUBULAR MEMBER INTO THE RADIATOR WITHOUT REMOVAL OF SAID CAP FROM THE FILLER NECK, SAID FILLER VALVE COMPRISING A HOUSING SECURED TO THE UPPER END PORTION OF SAID TUBULAR MEMBER IN COMMUNICATION THEREWITH AND PROVIDED WITH A FILLER PORT, A SPRING IN SAID HOUSING, AND A VALVE ELEMENT IN THE HOUSING BIASED BY SAID SPRING TO NORMALLY CLOSE SAID FILLER PORT, THE FILLER VALVE BEING OPENABLE BY EXTERNAL PRESSURE APPLIED TO SAID VALVE ELEMENT AGAINST THE RESILIENCY OF SAID SPRING, SAID NECK SEALING UNIT INCLUDING A GUIDE OF RESILIENT MATERIAL PROVIDED AT THE UNDERSIDE OF SAID CAP BODY AND HAVING SAID TUBULAR MEMBER SLIDABLE THEREIN, A CENTRALLY APERTURED DISC MEMBER PROVIDED AT THE LOWER END OF SAID TUBULAR MEMBER, AN ANNULAR NECK SEALING ELEMENT SECURED TO THE UNDERSIDE OF SAID DISC MEMBER, AND A COMPRESSION SPRING INTERPOSED BETWEEN SAID DISC MEMBER AND SAID CAP BODY. 